package jdbc;
/**
 * 别名
 */
import javax.jws.soap.SOAPBinding;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Map;

public class JDBCDemo6 {
    public static void main(String[] args) {

        try(
            Connection connection = DBUtil.getConnection();)
        {
            Statement statement = connection.createStatement();
            String sql = "SELECT COUNT(*) count " +
                         "FROM class c  " +
                         "JOIN student s ON c.id=s.class_id " +
                         "WHERE c.name='1年级1班'";
            ResultSet rs = statement.executeQuery(sql);
            while (rs.next()){
                int count = rs.getInt("count");
                System.out.println("人数:"+count);
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}
